In a recent South Park episode, we see two of the show's main characters, Stan and Kyle, rocking out to the video game Guitar Hero as a roomful of their friends watch, rapt.

As they're playing, Stan's father walks in, asks, "You kids want to see something really cool?" and starts to play an electric guitar.

For a moment, the room is dead silent. Then, Stan asks, incredulously, "Dad, what are you doing?"

"I can actually play a lot of these songs on a real guitar," the father responds. "Want me to show you boys how?"

Stan spits back, "That's stupid, Dad."

Well, maybe not, say guitar teachers. In fact, the immense popularity of the hit franchise--the third iteration of the game, Guitar Hero III, brought in $115 million during its first week on the market--may be the best thing that has happened to the instrument, to rock 'n' roll, and to guitar instructors, in a long time.

"I have an overwhelming feeling that my business is safe for years to come when I see kids playing Guitar Hero," said Dan Emery, owner of New York City Guitar School. "These kids are really enjoying playing Guitar Hero, and they're really being turned on to old classic rock" via the game.

Emery said he actually sees Guitar Hero as perhaps the best recruitment tool his school could have asked for.

Credit: South Park Studios

In the South Park episode "Queer-o," Stan and Kyle entertain their friends by playing Guitar Hero.

"I fully expect that (kids who play the game) will get into their twenties and they will have disposable income and they will decide to actually play guitar and they're going to call us up," he said.

Exact numbers of Guitar Hero-fueled converts to the real thing (kids or adults) are hard to come by. But something at work here clearly could be the most powerful advertisement for the guitar since the hit Richard Linklater movie School of Rock.

In that film, Jack Black plays a teacher who, through sheer passion for music, turns a class of rock-illiterate elementary school students into a head-bobbing rock band. After the movie came out, San Francisco guitar teacher Jay Skyler said his roster of young students exploded overnight.

"All of a sudden, I had 9-year-old students," Skyler said, "because all of a sudden, everyone wanted a guitar."

But now, with Guitar Hero turning into one of the most successful video game franchises of all time, Skyler said it's not just kids who seem interested in playing the real instrument.

While some of his new adult students may not be willing to admit that the game drove them to him, he did suggest a definite cause and effect.

"My adult students, they don't want to cop to it," Skyler said of being Guitar Hero fans, "but they're all, 'Have you played the game?'"

The immense popularity of Guitar Hero does worry some of Skyler's fellow guitar teachers, who fret that the game may deter kids from being interested in picking up the real instrument. But Skyler doesn't share that concern, instead feeling that the long-term outcome will be positive.

"Basically, it's getting more kids into guitar," Skyler said. "So if you're a guitar teacher, or a band, you have to love it. They'll play with the toy for a while, but after awhile, they'll want the real thing."

There are those, of course, who believe Guitar Hero signals a death knell for real guitars.

"It's going to kill music," said San Diego bass instructor David Hilton. "It seems to me that as long as (Guitar Hero fans) can get really, really good playing this console, (and) it's not really easy to play (a real) instrument," that the guitar is dead.

"When a kid gets filled with the fire of rock 'n' roll, they're going to practice four hours a day. Desire drives the guitar business."

--Dan Emery, owner, New York City Guitar School

But Hilton's fears may well be in the minority, and the enthusiasm of teachers like Emery and Skyler indicate that there's a real chance the ultimate result of millions of people getting hooked on games like Guitar Hero and now Rock Band will be a new love of rock 'n' roll.

Part of the equation, Skyler said, is that Guitar Hero teaches rhythm.

"In the game, you have four buttons," he said. "You have to get them in time, in sequence. So in a sense, even though (you're) not learning the specific strings, you are building rhythm in a musical context, which is valuable."

Not only that, but the wide variety of songs included in the various editions of Guitar Hero may be opening up kids' ears to music they haven't previously been familiar with.

"It's also interesting kids in great bands of the past that they might not have been exposed to," Skyler said. "So I think we'll see a resurgence of rock. Rock 'n' roll is about fantasy. If you can go and you're having a good time (and saying), 'Hey, I'm jamming with Slash,' that's great."

Even more important, suggested Emery, is that the guitar is a unique instrument when it comes to the way people connect with it.

"The thing that drives guitar playing is not the same thing that drives violin playing (or) piano playing," Emery said. "It is the desire to connect with the spirit of rock 'n' roll, and anything that builds the spirit of rock 'n' roll is going to build the spirit of guitar."

And that, of course, is good for those in the business of teaching the instrument.

"When a kid gets filled with the fire of rock 'n' roll, they're going to practice four hours a day," Emery said. "Desire drives the guitar business. So I view (Guitar Hero) as a totally good thing."